simplify code, fix test, use CompletionUtil.findIdentifierPrefix()

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/CompletionSession.kt

@@ -98,13 +98,6 @@ abstract class CompletionSessionBase(protected val configuration: CompletionSess
     protected val bindingContext: BindingContext = resolutionFacade.analyze(position.parents().firstIsInstance<JetElement>(), BodyResolveMode.PARTIAL_FOR_COMPLETION)
     protected val inDescriptor: DeclarationDescriptor? = expression?.let { bindingContext.get(BindingContext.RESOLUTION_SCOPE, it)?.getContainingDeclaration() }
 
-    private fun singleCharPattern(char: Char): CharPattern {
-        return StandardPatterns.character().with(
-                object : PatternCondition<Char>(char.toString()) {
-                    override fun accepts(c: Char, context: ProcessingContext) = c == char
-                })
-    }
-
     private val kotlinIdentifierStartPattern: ElementPattern<Char>
     private val kotlinIdentifierPartPattern: ElementPattern<Char>
 
@@ -115,15 +108,15 @@ abstract class CompletionSessionBase(protected val configuration: CompletionSess
             kotlinIdentifierPartPattern = StandardPatterns.character().javaIdentifierPart()
         }
         else {
-            kotlinIdentifierStartPattern = StandardPatterns.and(StandardPatterns.character().javaIdentifierStart(), StandardPatterns.not(singleCharPattern('$')))
+            kotlinIdentifierStartPattern = StandardPatterns.character().javaIdentifierStart() andNot singleCharPattern('$')
-            kotlinIdentifierPartPattern = StandardPatterns.and(StandardPatterns.character().javaIdentifierPart(), StandardPatterns.not(singleCharPattern('$')))
+            kotlinIdentifierPartPattern = StandardPatterns.character().javaIdentifierPart() andNot singleCharPattern('$')
         }
     }
 
     protected val prefix: String = CompletionUtil.findIdentifierPrefix(
             parameters.getPosition().getContainingFile(),
             parameters.getOffset(),
-            StandardPatterns.or(kotlinIdentifierPartPattern, singleCharPattern('@')),
+            kotlinIdentifierPartPattern or singleCharPattern('@'),
             kotlinIdentifierStartPattern)
 
     protected val resultSet: CompletionResultSet = resultSet

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/CompletionUtils.kt

@@ -20,6 +20,8 @@ import com.intellij.codeInsight.completion.*
 import com.intellij.codeInsight.lookup.*
 import com.intellij.openapi.progress.ProcessCanceledException
 import com.intellij.openapi.util.Key
+import com.intellij.patterns.ElementPattern
+import com.intellij.patterns.StandardPatterns
 import com.intellij.util.PlatformIcons
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.descriptors.*
@@ -30,15 +32,11 @@ import org.jetbrains.kotlin.idea.util.FuzzyType
 import org.jetbrains.kotlin.idea.util.getImplicitReceiversWithInstance
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.psi.*
-import org.jetbrains.kotlin.psi.psiUtil.getReceiverExpression
 import org.jetbrains.kotlin.psi.psiUtil.parents
 import org.jetbrains.kotlin.renderer.DescriptorRenderer
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.DescriptorToSourceUtils
 import org.jetbrains.kotlin.resolve.DescriptorUtils
-import org.jetbrains.kotlin.resolve.scopes.receivers.ExpressionReceiver
-import org.jetbrains.kotlin.resolve.scopes.receivers.ReceiverValue
-import org.jetbrains.kotlin.types.expressions.ExpressionTypingUtils
 import java.util.ArrayList
 
 enum class ItemPriority {
@@ -353,3 +351,9 @@ fun LookupElementFactory.createBackingFieldLookupElement(
         }
     }.assignPriority(ItemPriority.BACKING_FIELD)
 }
+
+fun <T> ElementPattern<T>.and(rhs: ElementPattern<T>) = StandardPatterns.and(this, rhs)
+fun <T> ElementPattern<T>.andNot(rhs: ElementPattern<T>) = StandardPatterns.and(this, StandardPatterns.not(rhs))
+fun <T> ElementPattern<T>.or(rhs: ElementPattern<T>) = StandardPatterns.or(this, rhs)
+
+fun singleCharPattern(char: Char) = StandardPatterns.character().equalTo(char)

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/KDocCompletionContributor.kt

@@ -20,15 +20,11 @@ import com.intellij.codeInsight.completion.*
 import com.intellij.codeInsight.lookup.LookupElement
 import com.intellij.codeInsight.lookup.LookupElementBuilder
 import com.intellij.codeInsight.lookup.LookupElementDecorator
+import com.intellij.patterns.ElementPattern
 import com.intellij.patterns.PlatformPatterns.psiElement
 import com.intellij.patterns.StandardPatterns
 import com.intellij.util.ProcessingContext
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
-import org.jetbrains.kotlin.idea.caches.resolve.KotlinCacheService
-import org.jetbrains.kotlin.idea.caches.resolve.analyze
-import org.jetbrains.kotlin.idea.caches.resolve.getResolutionFacade
-import org.jetbrains.kotlin.idea.completion.KotlinCompletionContributor
-import org.jetbrains.kotlin.idea.completion.LookupElementFactory
 import org.jetbrains.kotlin.idea.kdoc.getParamDescriptors
 import org.jetbrains.kotlin.idea.kdoc.getResolutionScope
 import org.jetbrains.kotlin.kdoc.lexer.KDocTokens
@@ -38,7 +34,6 @@ import org.jetbrains.kotlin.kdoc.psi.impl.KDocName
 import org.jetbrains.kotlin.psi.psiUtil.getParentOfType
 import org.jetbrains.kotlin.psi.psiUtil.getStrictParentOfType
 import org.jetbrains.kotlin.resolve.BindingContext
-import org.jetbrains.kotlin.resolve.lazy.KotlinCodeAnalyzer
 
 class KDocCompletionContributor(): CompletionContributor() {
     init {
@@ -102,11 +97,14 @@ class KDocNameCompletionSession(parameters: CompletionParameters,
 
 object KDocTagCompletionProvider: CompletionProvider<CompletionParameters>() {
     override fun addCompletions(parameters: CompletionParameters, context: ProcessingContext, result: CompletionResultSet) {
-        val prefix = if (parameters.getPosition().getNode().getElementType() == KDocTokens.TAG_NAME)
+        // findIdentifierPrefix() requires identifier part characters to be a superset of identifier start characters
-            parameters.getPosition().getText().removeSuffix(KotlinCompletionContributor.DEFAULT_DUMMY_IDENTIFIER)
+        val prefix = CompletionUtil.findIdentifierPrefix(
-        else
+                parameters.getPosition().getContainingFile(),
-            null
+                parameters.getOffset(),
-        val resultWithPrefix = if (prefix != null) result.withPrefixMatcher(prefix) else result
+                StandardPatterns.character().javaIdentifierPart() or singleCharPattern('@'),
+                StandardPatterns.character().javaIdentifierStart() or singleCharPattern('@'))
+
+        val resultWithPrefix = result.withPrefixMatcher(prefix)
         KDocKnownTag.values().forEach {
             resultWithPrefix.addElement(LookupElementBuilder.create("@" + it.name().toLowerCase()))
         }

idea/src/org/jetbrains/kotlin/idea/kdoc/KDocTypedHandler.kt

@@ -25,7 +25,7 @@ import com.intellij.openapi.project.Project
 import com.intellij.psi.PsiDocumentManager
 import com.intellij.psi.PsiFile
 import org.jetbrains.kotlin.kdoc.lexer.KDocTokens
-import org.jetbrains.kotlin.kdoc.psi.impl.KDocLink
+import org.jetbrains.kotlin.kdoc.psi.api.KDoc
 import org.jetbrains.kotlin.lexer.JetTokens
 import org.jetbrains.kotlin.psi.JetFile
 import org.jetbrains.kotlin.psi.psiUtil.getParentOfType
@@ -58,7 +58,7 @@ public class KDocTypedHandler(): TypedHandlerDelegate() {
             return when (c) {
                 ']' -> {
                     // if the bracket is not part of a link, it will be part of KDOC_TEXT, not a separate RBRACKET element
-                    element.getParentOfType<KDocLink>(false) != null
+                    element.getParentOfType<KDoc>(false) != null
                            && (elementType == JetTokens.RBRACKET || (offset > 0 && chars[offset - 1] == '['))
                 }
 

idea/tests/org/jetbrains/kotlin/idea/kdoc/KDocTypingTestGenerated.java

@@ -17,7 +17,6 @@
 package org.jetbrains.kotlin.idea.kdoc;
 
 import com.intellij.testFramework.TestDataPath;
-import org.jetbrains.kotlin.test.InnerTestClasses;
 import org.jetbrains.kotlin.test.JUnit3RunnerWithInners;
 import org.jetbrains.kotlin.test.JetTestUtils;
 import org.jetbrains.kotlin.test.TestMetadata;